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Former Iraqi deputy prime minister Tariq Aziz was the sophisticated, intelligent face of a thuggish regime. He was known for his elegant English suits and a fondness for Cuban cigars.

But photos, obtained exclusively by NBC News, for the first time show Aziz as he lives now, in custody. It's a strikingly different image — Aziz appears frail in orange prison garb and plastic handcuffs.

David Kay — a former U.S. adviser in Iraq — spent months questioning Aziz and others. He says Aziz quickly turned on Saddam and could testify at any trial.

"He talks about direct orders to murder, to assassinate, to kill," says Kay.

NBC News has learned U.N. investigators probing corruption in the U.N. oil for food program were scheduled to question Aziz last week. That session was delayed for security reasons.

The U.N. investigation — led by former Federal Reserve chairman Paul Volcker — is looking into Saddam's alleged diversion of oil money that was supposed to go for food to U.N. officials and politicians in key countries.

U.S. officials say Aziz already has implicated the French and others, claiming payoffs were made with the understanding that recipients would support Iraq on key matters before the U.N.